So the new transom brackets each have two 1/2" diameter holes (not countersunk). The old transom brackets had countersunk holes sized for a 3/8" bolt, which was received in a metal plate laminated in the transom (it appears). Are you guys just using 3/8" hex head tap bolts (with a 3/8" washer) in the 1/2" new bracket holes? I'm concerned about the platform slipping up/down relative to the bolts? If not 3/8" tap bolts, what are you guys using? Thanks!